Assessment of hepatic VX(2) tumors with combined percutaneous transhepatic lymphosonography and contrast-enhanced ultrasonographic imaging.

AIM To evaluate the feasibility and efficacy of percutaneous transhepatic lymphosonography (PTL) as a novel method for the detection of tumor lymphangiogenesis in hepatic VX(2) of rabbits and to evaluate combined PTL and routine contrast-enhanced ultrasonographic imaging for the diagnosis of liver cancer. METHODS Ten rabbits with VX(2) tumor were included in this study. SonoVue (0.1 mL/kg) was injected into each rabbit via an ear vein for contrast-enhanced ultrasonographic imaging, and 0.5 mL SonoVue was injected into the normal liver parenchyma near the VX(2) tumor for PTL. Images and/or movie clips were stored for further analysis. RESULTS Ultrasonographic imaging showed VX(2) tumors ranging 5-19 mm in the liver of rabbits. The VX(2) tumor was hyperechoic and hypoechoic to liver parenchyma at the early and later phase, respectively. The hepatic lymph vessels were visualized immediately after injection of contrast medium and continuously visualized with SonoVue during PTL. The boundaries of VX(2) tumors were hyperechoic to liver parenchyma and the tumors. There was a significant difference in the values for the boundaries of VX(2) tumors after injection compared with the liver normal parenchyma and the tumor parenchyma during PTL. CONCLUSION PTL is a novel method for the detection of tumor lymphangiogenesis in hepatic VX(2) of rabbits. Combined PTL and contrast-enhanced ultrasonographic imaging can improve the diagnosis of liver cancer.